title: Study of erythromycin A decomposition products in aqueous solution by solid-phase microextraction/liquid chromatography/tandem mass spectrometry.
abstract: The decomposition of erythromycin A (EA) in aqueous solution was examined in the pH range 2-13 by means of combined solid-phase microextraction (SPME) and liquid chromatography/electrospray ionization tandem mass spectrometry. Degradation of EA, especially at lower pH values (pH < or = 3), was very rapid and yielded a wide variety of decomposition products. Identification of these degradation products was achieved by means of tandem mass spectrometry in the product ion and precursor ion scan modes. Anhydroerythromycin A was shown to be the major reaction product in both acidic and basic solutions. Among the different SPME fibers investigated for extraction from aqueous solutions, polydimethylsiloxane/divinylbenzene exhibited the best performance for EA and its degradation products.
authors.affiliation: Institute for Marine Biosciences, National Research Council, Halifax, Nova Scotia, Canada.
authors.forename: D A
authors.initials: DA
authors.lastname: Volmer
authors.forename: J P
authors.initials: JP
authors.lastname: Hui
mesh_terms: D002855:Chromatography, Thin Layer; D004355:Drug Stability; D004917:Erythromycin / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D012996:Solutions
chemical_list: D007202:Indicators and Reagents; D012996:Solutions; D004917:Erythromycin